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JulyZS, 1925. #1,547,382' C f A A. E GQURDIER ET AL THERMOSTATICELECTRIC MOTOR PROTECTION Filed Jan. 13, 1322 l 2 sheets-sheet 1 EEEM.ef

nur die? A. E. GOURDIER ET' Al.

THERMOSTATIC ELECTRIC MOTOR PROTECTION July 28 1925.

A Filed Jan. 13, 1922 2 Sheets-Sheet 2 gglnsul-L and EenreM.EnurdiEr1.

Patented July 28, 1925.

UNITED STATES 1,541,382` PATENT OFFICE. A

RTHUR E. GOUBDIEB, CHARLES EGGLESTON, AND GEORGE M, GOURDIEPJ; 0FSM'Q'TA. CRUZ, CALIFG'RNIA.

TEERMOSTATEC EEEGTRIC-MOTQR PROTECTION.

Application filed anuary 13, 1922. Serial No. 528,921.

To @ZZ whom it may concern.' y Be it known that We, Aert-run E.Goniininn, @Hannes B. lEGoLnSToN, and Gannon M'. Germanien, citizens ofthe United States, residing at Santa Gruz, in the county ci Santa Crue,California, have invented certain new and useful improvements inTherincstatic Electric-Motor Protection, of which the tollovving is aspecicat-ion.

his invention relates to motors ci? Ae electric type, and the primaryobject the invention is to provide a novel protecting system forelectric motors for opening the circuit When 'the motor becomesoverheated from any cause, thereby preventing the hurriingout ci themotor and the consequent saving of time, lahor and money incident to therev-vinding of 'the iields and armature thereof.

`Protecting devices ior motors have already heen constructed in the artand are in use on the market, hut these devices merely include switchesfor opening the circuit,

when the current rises or alls aho've or he-- low a predetermined valueand do not contemplate means for permitting the opening oi? the circuitwhen the motor becomes oven heated for internal reasons, such as hothearinns, the armature scraping against the eld coils and the like.

is therefore another primeohgect ci the invention to-provide meanssensitive to heat incorporated directly 4with the motor for opening thecircuit, when the motor becomes overheated any reason,.loeyond a prede1terrnined degree, thereby eilectively preventing the burning out ci themotor from any cause. f 1

.A 'further object orIl the invention is the provision or a plurality ofthermostatic switches, einhedded or associated with the stator orlaminated held frame of a motor at advantageous points, and connected inseries with a no voltage releasenso thatvvhen the motor becomesoverheated from any cause, the current will be broken through the novoltage releasecoil Winding, causingr the starting switch toautomatically return to its open or starting point. l

A further object of the invention is the' provision o ,novel means forincorporating the thermostatic switches inthe circuit and in the stator,said thermostaticswitches being disposed in ockets or openings extendingparallel Wit the slots for the windings and in relative close proximitythereto, so

that any heat generated Will loe transmitted readily to the saidthermostatic switches.

A stili further object of the invention is to provide a novel protectingdevice or rnc-J ltors of the above character, which Will he durable andefficient in use, and one which can hey incorporated With existingmotors as Well as those in the course of manui'facture.v

W ith these and other objects in View, the

invention consists in the novel construction,

arrangement and formation oi" parts, as 'will oe hereinafter morespecifically described, claimed and illustrated in the accompanyingdrawings, Jforming a part o this specification, in which drawings:

Figure i is a diagrammatic View of the Wiring circuit for an electricmotor showing the improved motor protecting system incorpcratedtherewith.

lfifrure 2 is a iraementar side elevation 'l a n b de J l g or therraine or core oi the ield illustrating the position and arrangement ofone oithe therniostatic switches in relation thereto.

Figure 3 is an end elevation of a motor,

partly in section, sh'ovving'one of the 'therincstatic switches in theield thereof.

Figure i is an enlarged fragmentary trans verse section through thelarninations ci? a motor i'ield showing the thermostatic switch and themeans of incorporating the saine with the said eld laminations, the viewheing talren on the line 4 4 of Figure 5.

Figure 5 is a section similar to Figure 4,

taken on the line 5-5 of Figure e, showing a plan view ci one of thetlierinostatic switches.

Referring to the drawings in detail, Wherein similar reieerencecharacters designate corresponding parts throughout the several views, Aindicates an induction nuoto B, the circuit therefor; and C, theimproved protecting device incorporated with the motor A and the circuitB. `f v The motor A' can be of any lpreferred type or size, and as shownincludes the main frame 10, and the eld frame 11 provided with crossslots 12 for the eld coils 13. The field frame is connected to the mainframe in any referred manner, and the main frame may e provided with endplates 14 carrying bearings 15 for supporting the armature shaft 16 ofthe armature 17. 'The field frame 11Y is provided at quarters withtransversely extending openin s 18, in which are adapted to be positionethe thermostatic Y by the switch lever 32.

the motor.

switches 25 forming a'part of the protecting The improved protectingsystem C insystem C. These thermostatic swltches are cludes thethermostatic switches 25 as herecarried by the eld frame in the plane ofthe tobefore stated, and each one of these therarmature 17 so that ifthe armaturey rubs on mostatic switches includes a base' the field polesthe heat caused by friction preferably formed of electrical conductingwill quickly be transmitted to the thermomaterial. The base plates aresecured to static switches. These openings 18l can be the inner wallsolf the opening 18 vand are, i

stamped into the laminations of the field preferably insulated. from theiield frame frame at the time of the forming thereof, or 11 by means ofstrips of insulation 51. Thev if the motor is of the usual type, theopenbase dplates 50, have riveted or otherwise seings may be bored intothe same. While cure thereto the active arms 520i the theronly fouropenings have been shown and mostats, and these arms are 'preferablyconsequently only four thermostatic switches, formed of electricconducting material hav.-

it is to be understood that more or less openv ing a relatively highco-eflicient of expan-r ings and thermostatic switches may be had,sion.v The free end of each -arm 52 is proif desired, according to thetype of the motor. vided with a platinum contact point 53, Theseopenings are disposed at the upper and which adapted t0 eugftg Lplatinum 0011-. lower ends, and at the sides of the eld tact polnt 54carried by an adjustable post frame, outwardly ofv theeld coils 13, but55, which is threaded into engagement with relatively close to the innerwalls of the slots a supporting block '56, which can .be riveted 12. Theopenings 18 are formed relatively or otherwise secured to each baseplate 50.

`near the inner walls of the slots, so that the A suitable strip of'insulation 57 1s interthermostatic 'switches'25 disposed therein lposedbetween the block 56 andthe base will be readily ailect'edby heat formedin t lock from each other. The active arm 52 The circuit B consists or'apair of line ofthe thermostatic switch is so formed as to 'wires 20 and21 which mayflead from lany normally hold the contactpoint 53 intoensuitable source of power and these line Wires gagement wlth thecontact polnt 54 and to -have interposed therein any suitable typeofmove the contact point 53 away from the knife vswitch- 22. `The wire `20leads directly contact point 54 when the same isaiected to one bindingpost 23 of the motor, while. by heat, of a predetermined degl'e, Whichthe other wire 21 leads to a binding post can be determined by the`manufacture of 24 of the starting boxfor switch 26 of the the mOtOl-These theI'mOSt-tl SWlGhBS 25 motor. This switch is of the usualytypeand arej connected in series, by relatively short 10U embodies the11o-voltage release 27 and this wires 60, and one end thermostaticswitch is gwn-,Chaud mrvoltagq release, willgonly be connected with thewire 43, kwhile the other briefly described. f 'L The starting switch 26includes the usual base plate 28, on` which is mounted the the wire 39.p

In operation ofthe improved protecting rheostat 29, which includes anypreferred System, the motor is ystarted in the usual endthermostatic`switch 'is connected withnumber of contact buttons 30 connected byway,-that is, the starting switch leverl32 the various resistance coils31 and a switch` is gradually moved over thecontact buttons lever 32,which is normally held open or in '30 and toward the no-voltage releaseand to its olf position against the stop 33 by a spring the innermostcontact button. At this time, 34. This switch lever is connected to the-the armature 37 of the electromagnet 27 binding post 24 by a suitablewire 35. The will be in engagement with the electromaginner contactbutton 30 of the rheostat 29 is net and this magnet` will becomeenergized electrically connected to one terminal of the and hold thelever in its closed position no voltage release 27 by a wire 27. The noagainst the tension of the spring 34. 'When voltage release simplyconsists of an electrothe switch lever 32 is moved over to its magnet,the armature 37 of which is carried operative position, the current willflow The other terminal through the wire 20 to of the electromagnet hasconnected thereto a the ymotor and from the wire 39 which is connectedwith the pro- .thelwire 41 to the binding tecting system C which -willbe hereinthe binding post 42 the current passes. to after morespecifically described. The other the rheostat and when' the switchlever binding post 40 of the motor has connected 32 is in engagementwith one of the contact thereto the wire 41, which is in turn connectedto the other bindin post 42 of the starting switch 26. This bindingpost, in

turn, has 'a wire 43 connectedtherewith,

which is connected with the protecting system Cf The no voltage releasemay be shuntlel by a small resistance 45 with the A wire points of therheostat the current will pass through this arm and through the wire 35to the contact post 24 and through the wire 21 back to the switch. Acertain portion of the current will be held back by the resistance 45and this current will pass through the wire 43 and, through thethermostatic switches 25 and wire 39- to the-no voltage release magnet27 and 27 to the inner Dcontact post of the rheostat. It will thus beseen that the no voltage release magnet will be energized and will actupon, its armature 37 carried bythe switch lever 32 toretain the switchlever in the set position. If the motor becomes overheated from anycause beyond a predetermined degree, one or all 'of the thermostaticswitches will be operated, thus opening the circuit through the novoltage release 27, allowing the switch lever 32 to move automaticallyback to its off position against the stop 33 by the spring 34 and openthe circuit through the motor. This will effectively prevent injury to,the

motor and prevent the windings of the motor from being burned out. Itcan be seen that the thermostat-ic switches are disposed fin :the planeof the armature to be readily affected -by heat, if the heat isgenerated from frictional contact between the thermostaticswitch carriedentirely within l said field frame, in the ,plane of the stator.

2. An electric motor including a stator having a field frame ando0ils,-an amature, and a thermostatic switch carried entirely Withinsaid field frame, in the plane of the stasor land outermost with respect`to the co1 3. 'Ihe combination with an electric motor l including astator having openings formed 40 transversely therethrough in relativelyclose proximity with the inner face thereof, of a plurality ofthermostatic switches disposed in said openings.

4. The combination with an electric motor including a stator havingslots therein for the lield coils, of a -thermostatic switch embedded inthe stator outwardly of the said lots, and intermediate the side wallsof the ots.

5. The combination with an electric motor including a statory havingslots therein for the field coils and an opening extendin transversely`through the stator disposed outwardl of the slots and intermediate theside wa i thereof and in relatively close proximity to the inner Wall ofthe slot, of a thermostatic switch disposed in said open-4 ings.

6. The combination with an electric motor including a stator havingslots formed in the inner face thereof for the reception of theIieldcoils, and a transversely extending opening disposed 4outwardly ofthe slot intermediate the side walls thereof and in relatively closeproximity to the inner wall thereof, of' a thermostatic switch having abase plate and an active arm, a contact point "carried by the baseplate, a Contact int carried lby the active arm normally in engagementwith the first mentioned con-- tact point, the base plate beingI securedto the outer wall of the opening and the active arm disposed inrelatively close proximity t to the inner wall of the o ning.

ARTHUR E. URDIER. CHARLES B. EGGLES'IN. GEORGE M.' GOURDIER.

